Same Tree-identical tree check

 Given the roots of two binary trees p and q, write a function to check if they are the same or not.


Two binary trees are considered the same if they are structurally identical, and the nodes have the same value.


 


Example 1:




Input: p = [1,2,3], q = [1,2,3]

Output: true

Example 2:




Input: p = [1,2], q = [1,null,2]

Output: false

Example 3:




Input: p = [1,2,1], q = [1,1,2]

Output: false

 


Constraints:


The number of nodes in both trees is in the range [0, 100].

-104 <= Node.val <= 104


/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode() {}
 *     TreeNode(int val) { this.val = val; }
 *     TreeNode(int val, TreeNode left, TreeNode right) {
 *         this.val = val;
 *         this.left = left;
 *         this.right = right;
 *     }
 * }
 */
class Solution {
    public boolean isSameTree(TreeNode p, TreeNode q) {
       
         // Case 1: Both nodes are null
        if (p == null && q == null) return true;

        // Case 2: One of them is null
        if (p == null || q == null) return false;

        // Case 3: Values don't match
        if (p.val != q.val) return false;

        // Recursively check left and right subtrees
        return isSameTree(p.left, q.left) && isSameTree(p.right, q.right);


    }
}

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